Engine



Nov. 22, 1938. c. 5m 2,137,730

ENGINE Filed Aug. 16, 1937 Sheets-Sheet 1 Nox r. 22, 1938. c. F SMITH 2,137,730

ENGiNE Filed Aug. 16, 1937 s Sheets-Sheet 2 Nov. 22, 1938.

C. F, SMITH ENGINE Filed Aug. 16, 19's? 8 Sheets-Sheet 3 Nov. 22, 1938. Q SMITH 2,137,730

ENGINE Filed Aug. '16, 19:7 8 Sheets-Sheet 4 Nov. 22, 1938. c F. SMITH 2,137,730

ENGINE Filed Aug. 16, 19:57 a Sheets-Sheet 5 Nov. 22, 1938.

c. F. SMITH 2,137,730

ENGINE Filed Aug. 16, 19:57 a Sheets-Sheet e a \b e \Q @1149 w R s .Z/T//vro/c; o 4 /f'ro/rfi 07 717 Nbv. 22, 1938. c. F. SMITH 2,137,730

ENGINE Filed Aug. '16, 1957 8 Sheets-Sheet '7 NOV. 22, 1938. c SMITH 2,137,730

ENGINE Filed Aug. 16, 1957 8 Sheets-Sheet 8 Patented Nov. 22, 1938. j 2,137 730 UNITED STATES PATENT OFFICE Clifton F. srfi t lf lifmphis, Tenn. Application August 16, 1937, Serial No. 159,206 9 Claims. (01. 121-117) This invention relates to reciprocating engines Fig. 8 is an elevation looking in the direction employing a plurality of cylinders and pistons, of the arrow VIII of Fig. 6. the impulses for which pistons maybe furnished Figs. 9 to 16, inclusive, are diagrammatical either by steam from an external source, or by views showing the sequence of movements of the internal combustion. various parts of the engine shown in Figs. 1 to 5, 5

The present embodiment, which is especially inclusive, a single cylinder, a single piston, and adapted for aeronautical purposes, has been cona single piston rod having been substituted for fined, both in the drawings and the specifications, e pa o y n Piston and Piston rods of to an internal combustion engine. It will be 1 ;a distinctly understood, however, that the coni s-1 to ,1n usiv show di ammat a y struction outlined in a number of the claims is the Sequence of movements f the Various Parts as readily applicable to a steam engine and is the type of engine Shown in s- 6 t0 8, n-

intended to be so construed. clusive, single pistons, cylinders and piston rods It primarily relates to an engine construction having been Substituted Pairs 88 in 8 9 i in which the stroke is relatively long as compared to II with the bore of the cylinder and t th means by Referring now to the drawings, and particular-' Which t e transfer of power impulses of the pigiv to Figs. 1 to 5, inclusive, l0, II are a pair of ton to the crank shaft i accomplished opposed cylinders having a common longitudinal The primary object of th invention is to axis. i2, 13 are a second pair of cylinders having vide an engine which i simple in construction, also a common axis, these four cylinders being In durable, light in weight and capable of pmduc connected to a crank case M and constituting one ing maximum power with minimum vibration group of cylinders. I6, I! and I8 are three of the A further object is t provide novel means in four cylinders of a similar group of cylinders a long stroke cylinder construction for transfer- Spaced laterally from the first group and ring the power-impulses of t (gyhnders to a nected to the same crank case I 4 which, how- 5 crank shaft, and to provide such a means which ever, is shown in two parts, the longitudinal axes is adaptable to a multiple cylinder construction. the eight cylinders being parallel- The The means by whi t foregoing and other inders ill to I13, inclusive, are respectively proobjects are accomplished and the method of vided with pistons and these Pistons b their accomplishment will readily be understood having the usual Piston rings Cynnders' from the following specifications on reference to to inclusive and the unshown cylinder are th accompanying drawings, in similarly provided with pistons, none of which Fig. 1 is a sectional elevation at right angles are Shown but which are identical i construe the crank shaft taken on the line of Figs tion and action with pistons I 9 to 20, inclusive. 5; 3 and 4, and along the longitudinal center line Piston l9 and are connected together by of one group of the cylinders of a multi-cylinder rigid plsifon rod and pistons and 22 by engine, in which all the cylinders are paraneL a similar piston rod 25.- 26 is a block, preferably Fm 2 1s a sectional elevation taken along the in two halves, in which a transcommuter-link n n n f s 3 n 4 and exterior to the pin 28 of a connecting rod, or transcommuter link same group of cylinders 29, is journalled. 30 are bolts securing the piston .131 3 a sectional taken along the line rOdS and to the and securing the III-I11 of Fig. 1. o halves of the block together to complete the link Fig. 4 is a sectional elevation taken on the line D n a At its pp d e link has a IV--IV of Figs. 1, 2 and 3, being along the crank bearing 3| which journals a crank pin 32. h 33 is shaft. a crank disk which carries the crank pin and Fig. 5'is an enlarged sectional elevation taken is integral with, or securely fixed on, a crank as on the line V-V of Fig. 4. shaft 34. The shaft 34 is journalled in a bearing Fig. 6 is a sectional elevation of a modified 35, carried by one head 36 of the crankcase M. form of the engine in which two groups of cylin- The transcommuter pin 28 projects through ders are assembled with their longitudinal, axes the block 26 and has secured to its projecting. at right angles, the view being taken as on line end a transcommuter arm 31. The arm 31 is VI-VI of Fig. 7. a I positioned parallelto the transcommuter link 29- Fig. Tie a sectional elevation on an enlarg and constrained to remain in such position, as scale taken as on the line VII-VH'o'f Fig. 6. by a key 38. 39 is a transcommuter arm pin projecting transversely from the transcommuter arm 31 at its opposite end.

The effective length of the transcommuter link 23 is identical with the crank pin radius and the effective length of the transcommuter arm 31 is double each of these.

The second group construction duplicates the first group, 50, 5| being the piston rods of the second group of cylinders. 52 is the journal block; 53 the transcommuter link pin; 55 the transcommuter link; 55 the crank disk; 55 the crank pin; and 51 the crank shaft. 50 is the crank shaft bearing and 53 the second crank case head. 30 indicates a fragmentary portion of a propeller secured to the shaft 51. BI is the transcommuter arm duplicating the arm 31, and 32 the transcommuter arm pin corresponding to the pin 33. Both the pin 33 and the pin 62 are hollow. They are coupled together, as by a bolt 03 on which at least one of them is free to turn, it being readily seen that a stud, secured in one of the pins and journalled in the other thereof, will accomplish the same purpose. The two pins 33 and 32 so coupled are preferably journalled in a shoe 54, which shoe is slidably mounted between guides 55, which guides are disposed at right angles to the longitudinal axes of the cylinders and of the crank shafts. The guides 65 are preferably carried by a diaphragm 55 which is disposed between the two halves of the crank case I4, these halves being flanged for the purpose. The crank case heads 36 and 53 and the intermediate diaphragm may be secured in any usual or well known manner, as by bolts, which to reduce the detail are not here shown.

l and "II are half time shafts for the group of cylinders I0 to I3, inclusive, and I2, 13 halftime shafts for the other group of cylinders.

Mounted on the shaft I0 and secured, as by a key I4, is a gear I5, and similarly mounted and secured on the shaft II is a gear I5, which gears both mesh with a pinion II of one half relative pitch diameter which is mounted on shaft 34 and secured thereto by a key 18.

Similar gears I9 and 80 and meshing pinion 0i are respectively secured on the half-time shafts I2 and I3 and the shaft 51. 32 is a distributor driven by the half-time shaft I0, which distributor is suitably wired to spark plugs 83 on the cylinders I0 to I3, inclusive. 3 is a second distributor suitably wired to spark plugs 35 on the other group of cylinders.

33 are cams mounted on the shaft I0, these cams being secured as by the joint key 3 I. 32 are spacer disks alternating with the cams 30. 33 are similar cams similarly secured on the shaft II, and 34 the alternating spacers. 35 is an enclosing housing. The cams '30 and 33 actuate the valves of the cylinders III to I3, inclusive, and a similar group of cams mounted on the halftime shafts I2, I3, actuate the valves of the opposite group of cylinders. I00 is a pivot pin on which is mounted a pair of levers, IOI, these levers depending past the cams 93. Preferably each of these levers has a heel I02, which projects between a pair of the disks 92 to position the lever along the pin I00, these heels not proiecting into the path of the cams 00. The lower end of each lever lies between a pair of the disks 34 and against a cam 33. I03 is an oppositely disposed pivot pin from which an additional pair of levers I04 depend, these levers lying on the opposite sides of the cams 33 and alternating with the levers "I, so that levers I engage others of the cam 33 than those engaged by the levers IOI.

I06 and I01 are additional pivot pins from which similar pairs of levers, I03, I03, extend upward on opposite sides of the cams 30. Each of the levers is connected by a link I I 0, a rod 1 I I, which passes out of the housing 95 through a stuffing box II 2, and by a flexible cable II3 to a rocker arm II4, which operatively engages the end of a valve stem II5, a similar cable and rocker arm being .provided obviously for each valve. H is a bracket supported at one end by the housing 95 and at the opposite end by a valve stem housing I", which projects from the head II8 of the cylinder I2, similar valve housings projecting from each of the other heads and similarly supporting additional brackets. II 9 is a pivot pin for the rocker arm Ill and for a second rocker arm I20, these two arms operating the intake and exhaust valves of the cylinder I2 and being guided in their movements bythe housing In.

The engine here shown is the four cycletype, each cylinder having an exhaust valve I30 and an intake valve I3I. I32 are the exhaust pipes and I33 the intake manifolds, which lead from the carburetors I34 to the cylinders.

In Figs. 6 to 8, inclusive, two groups of cylinders have been arranged with their axes at right angles instead of parallel, as before described. In this arrangement, designated as X motor, the

- cylinders, and many of the other parts, may be identical in construction and function with those heretofore described, and these parts have been given the same numbers with the letter A as a suflix.

IOA, IIA, I2A and I 3A are the cylinders constituting one group, and ISA, ISA, HA and I 8A are the cylinders constituting a second group at right angles, these groups being connected to ajoint crank case A. ISA, A, 2IA and 22A are the pistons of the first group, the pistons of the second group not being shown. Pistons ISA and 20A are connected together by a rigid piston rod 24A, and the pistons 2IA and 22A by a similar rod 25A. 26A is the journal block, the two piston rods and the block being rigidly secured together by bolts 30A. 32A is the crank pin, 33A the crank disk which carries this pin, and 34A the 'crank shaft which isjournalled in the bearing A, carried by one head 35A of the crank case A.

50A, 5IA are the piston rods of the second group of cylinders I5A to ISA; 52A is the halved journal block. 55A is the crank disk; 55A the crank pin, which has the same throw as the crank pin 32A; 51A the crank shaft and 59A the second crank case head.

The piston rods 24A, 25A are connected to the crank pin 32A through a .transcommuter link I50, one end of which is journalled on the crank pin 32A. Integral with. and projecting from the opposite end of the link I50, is a transcommuter link pin I5I, which is journalled in the journal block 20A.

The piston rods 50A, 5IA are connected to the crank pin 58A through a transcommuter link I52, one end of which journals on the crank pin 58A. Integral with the opposite end of the link I52 is a transcommuter link pin I53, which is journalled in the journal block 52A.

Link pins III and I53 are integrally secured to a transcommuter bar I53, this bar and the links I50, I52 being thereby joined into a unitary transcommuter. In this transcommuter the center opposed cylinders, having a common longitudinal lines of the pins IiI and I5! and ,0! the bearings for the crank pins 32A, 56A lie in the same plane and are parallel, the distance between the pin ,I and its related bearing for the pin 32A, and

. the distance between the pin I53 and its related bearing for the pin 56A, are each equal to-the crank radius of these pins, and the distance I5I and I53 is equal to twice 1 unit and that an engine of this time maybe so built. It will also be understood that single axis, maybe used instead of opposed pairs as shown, particularly where two cycle or steam is used. Advantage has been taken of this fact I to simplify the diagrammatic drawings, Figs. 9 to 16, inclusive, of the parallel cylinder type and the drawings 1'7 to 21, inclusive, of'theiX motor type. In Figs. 9 to 16, -the pair of cylinders III,

I2,-are represented by a single cylinder C, cylinders II, I3 by cylinder D, cylinders I5, H by cylinder E,-'and cylinder I 6, III by cylinder F;

similarly each pair of pistons is representd by a single piston G, H, J, and K, respectively, and each pair of piston rods by'a single rod Nfand M, respectively. The crank disks 33 and 55 have been replaced by their equivalent crank similarly numbered.

In Figs. 17 to 21, inclusive, N, P, Q and R are cylinders representing the pairs of cylinders;' S,

T, U and Vthepistons and W and Y the piston I Crank arms 33A and 55A have been used instead ot the equivalent crank disks.

t Operation of parallel cylinder motor the impulse from a fired charge in the cylinder II. At the same time a charge is being compressed in cylinder In, a charge is being drawn 'into cylinder l3 through intake valve I3I, and a spent charge is being exhausted from cylinder I2.

As the block 28 moves toward the crank shaft 34, the transcommuter link 28 forces the crank pin -32 upward turning the shaft 34. Concurrently the shoe 64 is moved by the pin 39 outward be- 5 tween the guides 65, and at right angles to the line of piston travel. At one end of the stroke either the cylinder 20 or 22 gives a power-impulse,

and at the opposite end, one of the pistons I9, 2 I, ves an impulse.

e complete cycle of operation thus accomplished is .diagrammaticallyshown in Figs. 9 to to, inclusive. In Fig. 9 all the pistons are at one or the other ends of their respective -strokes, piston H-and piston J being ready to move toward the crank shafts 34,51, and pistons Gand K beving correspondingly in position, to begin movement away from the shafts. The crank arms 33 and 55 are omdead center and all pins in line;

As movement begins piston-impulse acting through transcommuter links 29 and 54- on crank arms 33, 65, turns them respectively counter clockwise and clockwise, In Fig. 10, the block 26 and thepin journalledtherein (pin 2B, Figs. 1.

. and 3) have been moved by piston H and rod L arms commuter link 29. have moved the crank arm 33,

forty-five degrees fromits first-shown position.

Similarly piston J, through rod M, has-moved block 52 and its journalled pin toward thecrank shaft 51 (aligned with shaft 4), and through the transcommuter link 54 has moved the arm forty-five degrees also, though in opposite relative direction. In these movements tra'nscom- 'muter arms 31- and GI have shifted the transcommuter arm pins 39 and 62 outward along the guides 65, and the pins 39 and 62 being coupled together by the bolt 63 (Fig. 3) and being "journalled in a joint shoe 64, are compelled to move concurrently and to interchange power-impulses and timing between the two piston groups and their shafts, providing a meanswhereby the power of both groups may be available from either the shaft 34 or the shaft 51. 5

v In Fig. 11 the two crank arms 33, 55 reach a ninety degree position and the'transcommuter arm pins 39, 62 the outer limit of their travel in the guides 65; the pistons have reached midstroke and are travelling twice as fast as the crank pins.

In Fig. 12 both crank shafts-have travelled one hundred and thirty-five degrees, and the coupled transcommuter-arm pins 39, 62 are returning along the guides 65.

In Fig. 13 one hundred and eighty degrees have been reached, the transcommuter-arm pins 39, 62 are aligned with the crank shafts 34, 51 and 'moving from above to below the same, and the power-impulses have transferred from cylinder D to cylinder C, andirom cylinder E to cylinder In Figs.'14, 15 and 16 the cycle continues, re-

turning to that shown in Fig. 9, the action corresponding tothat' of Figs. 9 to 12, respectively.

Referring to Fig, 11 or Fig. 15 (the crank arms.

being at ninety degrees) it will be noted that the transcommuter link 29 overlies the crank arm 33,

so that the transcommuter link pin journalledf in the block 26 (the pin 28 of Figs. 1 and 3) is arm 31, and the guides 65, toturn the shaft 34;

the crank arm as and the link 29, the link pin turning in the block 26 and transmitting no move-- ment to the piston rods or pistons, though obviously movement of the pistons would shift the block 26 and impart movement to the crank arm and shafts, and for proper action the transcommuter arm 31 is essential.

Operation of X motor The rigid assemblycomprising the four pistons I9A to 22A, the=piston rods 24A and 25A and the journal block 26A, move as one unit under suecessive impulses on the four pistons, and the cross positioned assembly moves similarly.

In Fig. 6 piston 20A is shown as moving downward and toward the left under the action of a fired charge; piston. I9A as compressing an additional charge; piston 22A as drawing in a charge; and piston 2 IA as exhausting a fired charge, thus giving two impulses each revolution for these four cylinders and the additional four cylinders I5A to ISA giving" two additional impulses per revolution.

In Fig. 17 piston S, acting through piston rod W" on journal block 26A and transcommuter pin I5I, transmits power through the transcommuter link I50 to the crank arm 35A and to the crank shaft 34A, and throu'gh the transcommuter bar Y on link pin ISA, the transcommuter link pin I53, the transcommuter link I52 to the crank arm A and the crank shaft 51A. Concurrently expansion in cylinder R acting through piston V and piston rod I53, adds power in the same direction.

In Fig. 18 the crank arms 33A, A have moved forty-five degrees from the position shown in Fig. 17, piston S continues its thrust at increasing angularity with regard to transcommuter link I II, and piston V approaching the end of its stroke is still exerting thrust on pin I53.

In Fig. 19 crank shafts 33A and 55A are at ninety degrees to their original position and all pins are again in alignment. Piston V has completed its stroke, Piston T is in firing position and becomes the primary power piston; and piston S is at mid-stroke exerting its thrust at right angles to transcommuter link I50.

In Fig. 20 the crank arms have completed one hundred and thirty-five degrees of movement vfroni Fig. 17. Piston S is approaching completion of its expansion stroke. Piston T is acting under expansion. Piston U is approaching the end of the compression stroke.

In Fig. 21 the crank arm has completed one hundred and eighty degrees travel from the position shown in Fig. 17. Piston S has completed its expansion stroke, piston T is acting under expansion, piston U is in firing position and is the primary power piston; and piston V is on its compression stroke.

In the subsequent half cycle, pistons W and V successively become the primary power pistons establishing a continuous flow of crank shafts.

What I claim is:

1. An engine, including a pair of axially aligned cylinders having each a piston reciprocally mounted therein, a piston rod rigidly connecting said pistons, a bearing on said rod, a shaft, a crank member connected to said shaft, a crank pin carried by said member, a link having one endjournalled on said crank pin and the opposite end rotatably secured to said piston rod bearing, the length of said link being equal to the crank radius, said link having a rigid extension of equal length, and a guide reciprocably receiving the end of said extension, said guide extending across the axis of said crank shaft at right angles to said axis and the axis of said cyl' inders and being a rigid part of said engines.

2. An engine including four cylinders in axiv I ally aligned pairs, said cylinders having each a piston reciprocabiy mounted therein, piston rods, each rigidly connecting a said pair of pistons, a bearing rigidly secured between and securing said piston rods together, a shaft extending at right angles from the axes of said cylinders and rods, crank means including a crank pin carried by said shaft, 9. link having'its opposite ends journalled on said pin and in said bearing, said link and said crank means being of equal length, said link having a rigid arm of equal length extending beyond said crank pin and a guide reciprocably receiving the end of said arm said guide being at right angles to said shaft and to the axes of said cylinders and being a. rigid part of saidengine.

3. An engine including a crank case, a shaft journalled insaid case, a crank member secured on said shaft, a crank pin projecting from said member, a pair'of cylinders in axial alignment extending from opposite sides of saidcrank case at right angles to said crank shaft, said cylinpower on both ried by'said crank case, at right angles to said.

crank shaft and to the axes of said cylinders, said means reciprocably receiving the end of said arm.

4. An engine, includinga crank case having axially aligned bearings at its opposite ends, crank shafts, each journalled in a said bearing, crank discs carried each by a said shaft, and crank pins of equal throw. carried each by a said disk; four cylinders in axially aligned pairs spaced apart, extending along parallel lines outward from said crank case, pistons reciprocably mounted, one in each said cylinder, a pair of piston rods, one for each said aligned pair of cylinders, each rod rigidly connecting the pistons .of its respective said cylinders, bearing means,.

ton bearing, said links having each a rigidly ex-.

tending transcommuter arm of.equal length, and means pivotally connecting the extended ends of said arms.

5. An engine, including a crank case having axially aligned bearings at its opposite ends,.

crank shafts; each journalled in asaid bearing, crank members carried each by said shaft, and

, crank pins of equal throw carried each by a said member; four cylinders in axially aligned pairs spaced apart, extending along parallel lines outward from said crank case, pistons reciprocably mounted, one in each said cylinder, a pair of piston rods, one for each said aligned pair of cylinders, each rod rigidly connecting the pistons of its respective said cylinders, bearing means, each carried by a said piston rod intermediate its length, transcommuter links, each equal in length to the throw radius of said crank pins, each connecting a said crank pin,and a said piston bearing, said links having each a rigidly extending transcommuter arm of equal length, means pivotallyconnecting the extending ends of said arms, and guide means rigidly secured to said crank case at right angles to said cylinder axes and crank shafts, said means extending laterally outward from the axis of said cranku shafts and reciprocably receiving said arm connecting .means.

6. An engine, including a crank case having axially aligned bearings at its'opposite ends, crank shafts, each journalled in a said bearing, crank members carried each by said shaft, and crank pins of equal throw carried each by a said mem-v her; four cylinders in axially aligned pairs spaced carried. by a said piston rod intermediate its length, transcommuter links, each equal in length to the throw radius of said crank pin, said links being journalled respectively each on a said crank pin and having each a transcommuter pin journailed in a said piston bearing, said links having each a rigidly extending transcommuter arm, said arms being of equal length, and rigidly secured each on a said transcommuter pin and respectively extending each from its said pin parallel with said transcommuter link twice the length of said link, each said transcommuter arm having a hollow pin projecting laterally at its inner end toward the complementary pin of the other said arm,-a bolt passing through said hollow pins and rotatably securing said pinstogether; a guide rigidly carried by said crank case and disposed between said arms, said guide being at right angles to said shafts and said piston rods, and a shoe reciprocably mounted in said guide and journalled on said hollow pins.

7. An engine, including a crank case having axially aligned bearings extending from opposite ends thereof, shafts, each journalled inv a said bearing, each said shaft having a crank disk within saidcase and a crank pin projecting from said disk, the crank radius of said pins being equal; a first pair of axially aligned cylinders secured to and projecting from said crank case in a plane at right angles to said crank shafts, a complementary pair of axially aligned cylinders secured to and projecting from said case in a spaced parallel plane, the said complementary cylinders, each said piston rod rigidly connecting its related pair of pistons, each said piston rod carrying a bearing intermediate its length,

a pair of parallel transcommuter links, each lying between a said crank disk and a related said piston rod and being journalled on a said crank pin, said links having a rigidly extending transcommuter 'pin extending therefrom through its respective said piston rod bearing, the effective length of said links being equal and equal to the crank radius; and a transcommuter connector rigidly secured to and joining the projecting ends of said transcommuter pins, said connector lying between said piston rods and parallel to both to and projecting from opposite sides of said crank case in a plane at right angles to said crank shafts, a complementary pair of axially aligned cylinders secured to and projecting from said case in a spaced parallel plane, the said cylinder axes being at right angles, each said cylinder having a piston reciprocably mounted therein; a pair of piston rods, one for each said aligned pair of cylinders, each said piston rod rigidly connecting itsrelated pair oi pistons, each said piston rod having a journal bearing midway its length and a transcommuter for coupling said crank pins to' their related piston rods, and the ,engine units thus formed together, said transcommuter, comprising a connector bar having a pair of pins adapted to journal in said piston rod bearings, said pins respectively being at opposite ends of said bar and extending rigidly in opposite directions at right angles therefrom, and a pair of links spaced from said bar, rigidly secured each to a said pin and extending along and parallel with said bar, each said link having a hearing adapted to journal a said crank pin, the length of said links being equal to the crank 'l8.d1ll$ and the length of said bar to the crank diameter.

9. An engine, including a crank case havin axially aligned bearings extending from opposite ends thereof, crank shafts, each journalled in a said bearing, each said shaft having a crank disk within said case and a crank pin projecting from said disk, the throw of said pins being equal, ailrst pair'of axially aligned cylinders secured to and projecting from opposite sides of said crank case in a plane at right angles to said crank shaft, a complementary pair of axially aligned cylinders similarly secured to and projecting from said case in a spaced parallel plane, the said cylinder axes being at right angles, each said cylinder having a piston reciprocably mounted therein; a pair of piston rods, one for each said aligned pair of cylinders, each said piston rod rigidly connecting its related pair of pistons, and having a journal bearing intermediate its length; a pair oi. links in parallel, each journalled on a said crank pin and having a pin, joumalled in a respective said journal bearing, the eifective length of said links being each equal to a crank pin radius, and means rigidly secured to said link pins, compelling said links to remain in parallelism, the effective length of said means equalling a crank diameter.

cmr'ron r. SMITH. 

